One of the most iconic images of small-town America in the ’50s was the drive-in restaurant with its always on-the-go carhops swirling around on skates, delivering hot dogs, hamburgers, shakes, and fries to their car-bound customers. It’s a vision not often seen anymore unless you catch a rerun of Happy Days—remember the Fonz?—but Sonic Drive-In, an Oklahoma-based fast-food chain with more than 3,500 locations around the U.S., still boasts carhops at a large portion of its stores. Sonic, which started in the postwar era, helped popularize the skating carhop and still holds an annual competition featuring its own employees. It also championed the car-side speaker technology that is used at millions of drive-thrus every day—the name Sonic came from “Service at the Speed of Sound,” an early slogan.

Its food, though, is not so sound, as the menu runs the usual gamut of almost everything fried, sticking to a menu straight out of the ’50s with loads of french fry, onion ring, tater tot, hot dog, hamburger, and milk shake options to glop up your arteries and grow your waistline. No salads can be found here, so your best bets are the usual and fairly boring grilled-chicken items and some halfway nutritionally decent breakfast bites. If you get desperate for vitamins and fiber, Sonic also offers the token apple slices that are popping up at lots of greasy fast-food joints these days.

Whatever you do, steer clear of the numerous milk shake, malt, Candy Slush, and Blast options it offers. For example, a “mini,” or 12 oz, Oreo Peanut Butter Shake runs 800 calories alone and boasts 65 grams of sugar, nearly double the recommended daily amount of 37.5g for men! And a small 16 oz Green Apple Slush with Rainbow Candy runs 360 calories, with a whopping 90g of sugar, or more than 20 tablespoons of the sweet stuff.

Sonic food options